1
2 // Copyright 2017 Peter Dimov.
3 //
4 // Distributed under the Boost Software License, Version 1.0.
5 //
6 // See accompanying file LICENSE_1_0.txt or copy at
7 // http://www.boost.org/LICENSE_1_0.txt
8
9 #include <boost/variant2/variant.hpp>
10 #include <boost/core/lightweight_test.hpp>
11 #include <boost/core/lightweight_test_trait.hpp>
12 #include <type_traits>
13 #include <utility>
14 #include <string>
15
16 using namespace boost::variant2;
17
18 #define STATIC_ASSERT(...) static_assert(__VA_ARGS__, #__VA_ARGS__)
19
20 struct X1
21 {
22 int v;
23
X1X124 X1(): v(0) {}
X1X125 explicit X1(int v): v(v) {}
X1X126 X1(X1 const& r): v(r.v) {}
X1X127 X1(X1&& r): v(r.v) {}
operator =X128 X1& operator=( X1 const& r ) { v = r.v; return *this; }
operator =X129 X1& operator=( X1&& r ) { v = r.v; return *this; }
30 };
31
operator ==(X1 const & a,X1 const & b)32 inline bool operator==( X1 const& a, X1 const& b ) { return a.v == b.v; }
33
34 STATIC_ASSERT( !std::is_nothrow_default_constructible<X1>::value );
35 STATIC_ASSERT( !std::is_nothrow_copy_constructible<X1>::value );
36 STATIC_ASSERT( !std::is_nothrow_move_constructible<X1>::value );
37 STATIC_ASSERT( !std::is_nothrow_copy_assignable<X1>::value );
38 STATIC_ASSERT( !std::is_nothrow_move_assignable<X1>::value );
39
40 struct X2
41 {
42 int v;
43
X2X244 X2(): v(0) {}
X2X245 explicit X2(int v): v(v) {}
X2X246 X2(X2 const& r): v(r.v) {}
X2X247 X2(X2&& r): v(r.v) {}
operator =X248 X2& operator=( X2 const& r ) { v = r.v; return *this; }
operator =X249 X2& operator=( X2&& r ) { v = r.v; return *this; }
50 };
51
operator ==(X2 const & a,X2 const & b)52 inline bool operator==( X2 const& a, X2 const& b ) { return a.v == b.v; }
53
54 STATIC_ASSERT( !std::is_nothrow_default_constructible<X2>::value );
55 STATIC_ASSERT( !std::is_nothrow_copy_constructible<X2>::value );
56 STATIC_ASSERT( !std::is_nothrow_move_constructible<X2>::value );
57 STATIC_ASSERT( !std::is_nothrow_copy_assignable<X2>::value );
58 STATIC_ASSERT( !std::is_nothrow_move_assignable<X2>::value );
59
main()60 int main()
61 {
62 {
63 variant<int> v;
64 BOOST_TEST_EQ( get<0>(v), 0 );
65
66 v.emplace<0>( 1 );
67 BOOST_TEST_EQ( get<0>(v), 1 );
68
69 v.emplace<0>();
70 BOOST_TEST_EQ( get<0>(v), 0 );
71 }
72
73 {
74 variant<int, float> v;
75 BOOST_TEST_EQ( v.index(), 0 );
76 BOOST_TEST_EQ( get<0>(v), 0 );
77
78 v.emplace<0>( 1 );
79 BOOST_TEST_EQ( v.index(), 0 );
80 BOOST_TEST_EQ( get<0>(v), 1 );
81
82 v.emplace<1>( 3.14f );
83 BOOST_TEST_EQ( v.index(), 1 );
84 BOOST_TEST_EQ( get<1>(v), 3.14f );
85
86 v.emplace<1>();
87 BOOST_TEST_EQ( v.index(), 1 );
88 BOOST_TEST_EQ( get<1>(v), 0 );
89
90 v.emplace<0>();
91 BOOST_TEST_EQ( v.index(), 0 );
92 BOOST_TEST_EQ( get<0>(v), 0 );
93 }
94
95 {
96 variant<int, int, float, std::string> v;
97 BOOST_TEST_EQ( v.index(), 0 );
98 BOOST_TEST_EQ( get<0>(v), 0 );
99
100 v.emplace<0>( 1 );
101 BOOST_TEST_EQ( v.index(), 0 );
102 BOOST_TEST_EQ( get<0>(v), 1 );
103
104 v.emplace<1>();
105 BOOST_TEST_EQ( v.index(), 1 );
106 BOOST_TEST_EQ( get<1>(v), 0 );
107
108 v.emplace<1>( 1 );
109 BOOST_TEST_EQ( v.index(), 1 );
110 BOOST_TEST_EQ( get<1>(v), 1 );
111
112 v.emplace<2>( 3.14f );
113 BOOST_TEST_EQ( v.index(), 2 );
114 BOOST_TEST_EQ( get<2>(v), 3.14f );
115
116 v.emplace<2>();
117 BOOST_TEST_EQ( v.index(), 2 );
118 BOOST_TEST_EQ( get<2>(v), 0 );
119
120 v.emplace<3>( "s1" );
121 BOOST_TEST_EQ( v.index(), 3 );
122 BOOST_TEST_EQ( get<3>(v), std::string("s1") );
123
124 v.emplace<3>( "s2" );
125 BOOST_TEST_EQ( v.index(), 3 );
126 BOOST_TEST_EQ( get<3>(v), std::string("s2") );
127
128 v.emplace<3>();
129 BOOST_TEST_EQ( v.index(), 3 );
130 BOOST_TEST_EQ( get<3>(v), std::string() );
131
132 v.emplace<3>( { 'a', 'b' } );
133 BOOST_TEST_EQ( v.index(), 3 );
134 BOOST_TEST_EQ( get<3>(v), (std::string{ 'a', 'b'}) );
135
136 v.emplace<3>( { 'c', 'd' }, std::allocator<char>() );
137 BOOST_TEST_EQ( v.index(), 3 );
138 BOOST_TEST_EQ( get<3>(v), (std::string{ 'c', 'd'}) );
139 }
140
141 {
142 variant<X1, X2> v;
143 BOOST_TEST_EQ( v.index(), 0 );
144 BOOST_TEST_EQ( get<0>(v).v, 0 );
145
146 v.emplace<0>( 1 );
147 BOOST_TEST_EQ( v.index(), 0 );
148 BOOST_TEST_EQ( get<0>(v).v, 1 );
149
150 v.emplace<1>( 2 );
151 BOOST_TEST_EQ( v.index(), 1 );
152 BOOST_TEST_EQ( get<1>(v).v, 2 );
153
154 v.emplace<0>();
155 BOOST_TEST_EQ( v.index(), 0 );
156 BOOST_TEST_EQ( get<0>(v).v, 0 );
157
158 v.emplace<0>( 4 );
159 BOOST_TEST_EQ( v.index(), 0 );
160 BOOST_TEST_EQ( get<0>(v).v, 4 );
161
162 v.emplace<1>();
163
164 BOOST_TEST_EQ( v.index(), 1 );
165 BOOST_TEST_EQ( get<1>(v).v, 0 );
166
167 v.emplace<1>( 6 );
168 BOOST_TEST_EQ( v.index(), 1 );
169 BOOST_TEST_EQ( get<1>(v).v, 6 );
170
171 v.emplace<0>( 3 );
172 BOOST_TEST_EQ( v.index(), 0 );
173 BOOST_TEST_EQ( get<0>(v).v, 3 );
174
175 v.emplace<0>( 4 );
176 BOOST_TEST_EQ( v.index(), 0 );
177 BOOST_TEST_EQ( get<0>(v).v, 4 );
178 }
179
180 return boost::report_errors();
181 }
182